This invention relates to a linear roller bearing for use in a linear motion part of a machine tool or industrial machine, and more particularly, a linearly moving guide bearing for arrangement between the grooves of two guide rails.
Linear roller bearings such as are shown in FIGS. 1 and 2 are already known. The roller bearing assembly, generally depicted by the numeral H are arranged between grooves C and D of two guide rails A and B opposed to each other. The guide rails A and B can reciprocate and move along the assembly. When the guide rails A and B move, the roller bodies fitted to the holder of the assembly H move a little with them.
In the assembly of H in FIG. 1, a roller body F is held so as to be rotatable in a holding hole formed in a base plate E. Further, the respective rollers F are reversed in the direction of inclination so as to alternately intersect at right angles with each other.
In the assembly H of FIG. 2 a ball G is rotatably held in a hole I formed in the base plate-shaped holder E. However, the plate E is formed with many holding holes I in a thin metal strip which holes are provided with a holding pawl J for holding the roller F or ball G inside each hole I. Therefore, in forming the hole I and the holding pawl J, the metal plate is likely to be bent or twisted.
Thus, a defect is created by which the plate is deformed so that when the plate E is arranged between the grooves C and D of the guide rails A and B, the plate E will rub against the guide rails A and B and an unreasonable force will be applied to the roller F or ball G. Consequently, it will be difficult for the roller F or ball G to smoothly rotate and it will be hard for the guide rails A and B to move. The longer the strip E, the more pronounced this defect becomes.
Another defect arises in the plate E shown in FIGS. 1 and 2, since the holding pawl J is formed directly in the holding hole I. Thus, even if one of the holding pawls is broken, the entire assembly must be replaced. Therefore, great waste occurs and this type of holder is uneconomical.